Spatial Variations in Straight- and Split-ticket Voting and the Role of Constituency Campaigning at New Zealand’s First Two MMP Elections: Individual-level Tests

Abstract

Elections held under the MMP system provide opportunities for substantial split-ticket voting, whereby electors support one party in the list contest but another in the constituency contests. At New Zealand's first two elections using this system—in 1996 and 1999—37% and 35% of the voters, respectively, employed a split-ticket strategy. Estimates of the amount of splitting in each constituency between each pair of parties—in a seven-party system on each occasion—have allowed the successful testing of hypotheses relating its volume to party prospects in the constituencies and the amount of local campaigning. These findings are replicated in comparable analyses at the individual scale using survey data.